ios 美元飘落效果的demo

demo功能：ios 美元飘落效果的demo 。

demo说明：美元飘落效果demo ，可以多指触控，触控点越多，飘落的美元面额越大。主要代码在：MainView.m中。

demo截屏：

demo代码说明：

[csharp]
- (void)onTimer
{
    UIImageView *dollarView;
    UIImage *dollarImage;

    // for effect... make it harder to get some of the other bill index's
    // if it does not pass criteria reset back to 1

    // double tap upside down for 5 Dollar bill
    if(billIndex > 2) {
        if (deviceTilt.y > 0.5f)
            billIndex = 5;
        else
            billIndex = 1;
    }
    else if(billIndex > 1) {
        if (deviceTilt.x > 0.5f)
            billIndex = 3;
        else if (deviceTilt.x < -0.5f)
            billIndex = 4;
        else
            billIndex = 2;

    }


    switch (billIndex) {
        case 2:
            dollarImage = [UIImage imageNamed:@"dol2.png"];
            break;
        case 3:
            dollarImage = [UIImage imageNamed:@"5dol.jpg"];
            break;
        case 4:
            dollarImage = [UIImage imageNamed:@"10dol.jpg"];
            break;
        case 5:
            dollarImage = [UIImage imageNamed:@"20dol.jpg"];
            break;
        default:
            dollarImage = [UIImage imageNamed:@"dollar.png"];
            break;
    }
    //以上是检测触点，并分配不同的美元图片
    // for effect only draw one 2 dollar bill by resetting billIndex
    if (billIndex == 2)
        billIndex = 1;
    //以下是动画部分的核心代码
    dollarView = [[UIImageView alloc] initWithImage:dollarImage];
    int scale = RANDOM_INT(1, 5);
    int width = 100*scale;
    int height = 44*scale;
    if(useEmitterRect) {
        dollarView.frame = emitterRect;
    //} else if (deviceTilt.x > 0.5f || deviceTilt.y > 0.5f || deviceTilt.x < -0.5f || deviceTilt.y < -0.5f) {
    } else if (deviceTilt.y > 0.5f) {
        dollarView.frame = CGRectMake(160 - (width/2), 490, width, height);
    } else if (deviceTilt.y < -0.5f) {
        dollarView.frame = CGRectMake(160 - (width/2), -(height+10), width, height);
    } else if (deviceTilt.x > 0.5f) {
        dollarView.frame = CGRectMake(-(width+10), 240-(height/2), width, height);
    } else if (deviceTilt.x < -0.5f) {
        dollarView.frame = CGRectMake(330, 240-(height/2), width, height);
    } else {
        switch (RANDOM_INT(0, 3)) {
            case 0:
                dollarView.frame = CGRectMake(-300, -300, 100*scale, 44*scale);
                break;
            case 1:
                dollarView.frame = CGRectMake(470, -150, 100*scale, 44*scale);
                break;
            case 3:
                dollarView.frame = CGRectMake(470, 630, 100*scale, 44*scale);
                break;
            default:
                dollarView.frame = CGRectMake(-150, 630, 100*scale, 44*scale);
                break;
        }
    }

    [self addSubview:dollarView];
    if(helpView)
        [self bringSubviewToFront:helpView];

    [UIView beginAnimations:nil context:dollarView];
    [UIView setAnimationDuration:2];

    dollarView.frame = CGRectMake(RANDOM_INT(-50, 370), RANDOM_INT(-25, 665), 100, 44);

    int radians = RANDOM_INT(0, 360) * 0.0174532925;
    [dollarView setTransform:CGAffineTransformMakeRotation(radians)];

    [UIView setAnimationDelegate:self];
    [UIView commitAnimations];

补充：移动开发 , IOS ,